phy.scie L1

• For the ancient greeks, the universe is stationary and is divided into two regions, Terrestrial and Celestial region.
• Terrestrial Region: consists of all things on earth that are made up of four elements; air, fir, water, earth.
• Celestial Region: includes all heavenly bodies beyond the moon, sun, stars and other planets are made up of the fifth substance called Quintessence.
• Terrestial motion is driven by force or the desire of the four elements to seek perfection.
• Aristotelian Universe: non-homogeneous, finite, spherical space.
• Celestial Region: natural motion is circular.
• Sublunary Region: Made of earth, water, air, and fire. Natural motion is downward or upward.
• Natural Motion: Terrestrial realm; made of the four elements. Upward or Downward.
• Voluntary Motion: according to Aristotle, --- was an innate characteristics of humans and animals. The cause of their motion was in themeselves because they have the will to move.
• Involuntary Motion: the characteristics of plants and minerals. They could not move because they do not have the will to do so. They could only move due to mechanical forces.
• After many years, Galileo Galilei contradicted Aristotle's ideas pf motion.